The pilot was attempting to complete a solo flight of at least one hour duration as part of the qualification for the issue of a C Gliding Certificate. Witnesses reported that during the winch launch, the glider lifted off too early, and then assumed the climb attitude before sufficient airspeed had been obtained. The pilot stated that she released from the winch cable when she became aware that the airspeed was too low. At about the same time the right wing dropped and the aircraft turned through about one and a half revolutions before impacting the ground with the right wingtip. The pilot had attempted to correct for the wing drop with aileron control inputs, which were ineffective at the low airspeed.

At a height of about 200 feet after take-off the right engine lost power. The pilot feathered the propeller and commenced a gentle left turn in order to return to the strip. He later advised that the aircraft began to sink towards some large trees and he was forced to increase the angle of bank in an effort to avoid them. Shortly afterwards the aircraft struck the ground heavily in an adjacent paddock about 1 kilometre from the strip. The engine failure was caused by jamming of accessory drive gearing as a result of the effects of excessive wear within a magneto. It was probable that a mandatory inspection of the magneto which fell due 84 flying hours before the accident, was not conducted. On take-off the aircraft weight exceeded the authorised limit, however following the engine failure the pilot was able to maintain straight and level flight. A cleared area of ground lay ahead and just to the left of the flight path but the pilot had considered the aircraft had sufficient performance capability to permit a return to the strip.

The pilot, who had only been in the area for four weeks, was carrying out a mail run from Mount Isa to Burketown, via Lorraine, Gregory Downs, Lawn Hill and Hell's Gate. Approaching Burketown the aircraft encountered a duststorm and the pilot became unsure of her position. After searching for some time without being able to find Burketown she flew north to the coast and located what she believed was the mouth of the Nicholson River. From there she intended to proceed to Escott Station, thence to Burketown. The Non Directional Beacon (NDB) at Burketown was unserviceable. The pilot tracked upriver until she saw a station alongside a road. She decided to land to fix her position. During the subsequent landing the left wheel of the aircraft entered a washaway on the road and the gear leg collapsed. It was determined that the pilot had misidentified the particular river. The temperature in the area was over 40 degrees Celsius and one of the passengers had been almost continually airsick since leaving Hell's Gate.

Circumstances:

Shortly after take-off, on the 33 degree Celsius day and close to the approved maximum weight, the right engine surged and lost power. The pilot completed his engine failure after take-off check list and looked for a landing site. The only suitable area, in the aircraft's flight path was the harbour. The aircraft was unable to maintain height and the pilot reported that it descended at 100 feet per minute until it struck the water. The pilot then retarded the left throttle and allowed the aircraft to ditch. The symptoms reported by the pilot indicated that there had been an interruption to the fuel flow to the right engine. The investigation found that the right hand electrical fuel boost pump was unserviceable. No other faults were found. The reason for the engine failure could not be determined. At the manufacturer's approved maximum weight of 3060 kilograms the single engine performance charts contained in the USA approved Flight Manual, indicate that the aircraft should climb at 230 feet per minute at 33 degrees Celsius. The Civil Aviation Authority had approved an increase in maximum weight to 3357 kilograms, however, the Australian approved Aircraft Flight Manual does not contain any single engine performance information. The USA manual does not contain any information on performance at the increased maximum weight. Practical experience indicates that a single engine AC500S should be able to achieve a positive, but minimal, rate of climb at the accident flight weight and temperature, if all other conditions are at their optimum. On this occasion wind conditions were turbulent, making accurate flying difficult and the aircraft was not able to achieve a positive rate of climb once the right engine had failed.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. There was an interruption to fuel flow to the right hand engine. It could not be determined whether the unserviceable electrical fuel boost pump contributed to the interruption.

2. The right engine lost power during a critical phase of the take-off.

3. Experience indicates that single engine performance in the prevailing conditions would have been marginal.

4. The pilot had limited experience on the Rockwell Commander 500S, and this coupled with the weight and weather conditions may have resulted in the aircraft not being able to achieve safe single engine climb.

In sunny conditions with clear visibility and a slight easterly wind drift, the pilot was spraying a paddock of thistles with a herbicide. He had inspected the job site on the ground two days earlier. Because of the mountainous terrain, the pilot flew a left hand racetrack pattern. The spray runs were flown at about ten feet above ground level. The fourth spray run was to the south and encountered clumps of trees. Near the end of the run, the outboard section of the right wing collided with a seven metre high tree removing about one metre of the top of the tree. Almost immediately the aircraft carried out a very steep climbing turn to the right and the engine noise diminished as if the pilot had closed the throttle. The aircraft then descended in a steep, nose down attitude. There was no witness to the aircraft's impact with the ground. Wreckage layout confirmed that it impacted the ground in a nose low attitude with wings almost level. There was no ground slide. For reasons unknown, the pilot did not dump the load of herbicide after hitting the tree. At ground impact the hopper burst out of the airframe and the fuel tank, containing an inner rubber liner, ruptured. The fuel ignited and the aircraft was destroyed by fire. Whether the aircraft became uncontrollable after the tree strike remains unknown. The aircraft was serviceable prior to impacting the tree despite confirmation of minor right wing damage after a previous tree strike on 27 October 1989 by the same pilot at a previous job site. A simulated spray run has since been flown over the same ground by an agricultural pilot flying instructor. The impacted tree was difficult to see because of a larger clump of trees in the immediate foreground. Also, it partially blended into a treed hill of similar hue about 500 metres beyond. There was no practical need to fly the run as low as ten feet and doing so would have been unnecessarily dangerous. It is possible that the pilot closed the throttle while mistaking it for the spray lever after the tree collision. The pilot had successfully flown sixteen hours of spraying operations in the same mountainous terrain during the week prior to the fatal accident.

The pilot and passenger were undergoing a full time flying training course to Commercial Licence standard, and had both recently obtained their restricted Private Pilots Licences (i.e. restricted to flight within the flying training area). On the day of the accident the pilot had spent the morning at lectures, and preparing for navigation exercises. After lunch he approached the Chief Flying Instructor and asked if he could take VH-FLF to the training area for an hour. This was approved and the pilot signed the flight authorisation sheet and entered the time 1340 hours on the sheet. There was no indication on the authorisation sheet that he intended to take a passenger, nor did he mention this to the Chief Flying Instructor. The pilot was later seen sitting in the aircraft, apparently awaiting the arrival of his passenger. There appears to have been no prior arrangement, other than a spur of the moment decision by the passenger, to go on the flight. The pilot called Archerfield Tower at 1351 hours and reported taxiing for the southern training area. At 1359 hours VH-FLF was cleared for takeoff. This was acknowledged by the pilot, and no further radio transmissions from the aircraft were heard or recorded. At approximately 1415 hours, witnesses heard the aircraft flying overhead. The aircraft was seen flying in a south-easterly direction in apparently normal flight, when the engine noise suddenly ceased. The aircraft was then observed descending in a steep spiral or spin from a altitude of about 2000 feet. The spiralling motion appeared to cease momentarily before the aircraft dived into the ground. The aircraft impacted the ground in a steep inverted nose down attitude. Indications are that the aircraft may have been recovered from the spiral briefly, before stalling and becoming inverted during the recovery at a very low height. No mechanical defects were found which may have affected the airworthiness of the aircraft, or which may have contributed to the development of the accident.

Circumstances:

The aircraft departed Narromine in company with three other gliders for a cross-country flight Narromine - Parkes - Condobolin - Narromine. Weather conditions were fine with good visibility but were otherwise difficult with weak and well-separated thermals being the only sources of lift. North of Parkes all four aircraft had descended to a low altitude. The other three pilots were able to use the weak lift to continue the flight but the pilot of VH-IUB decided that he was unable to continue and informed the other pilots by radio that he would land in a paddock. A south westerly wind of about five knots was blowing on the surface. The aircraft approached the paddock from the south west. In the latter part of the approach, at very low altitude, the pilot initiated a left turn to track away from trees at the edge of the paddock. During the turn the left wingtip struck the ground initiating a cartwheel motion. The fuselage impacted heavily in a steep nose-down attitude. The aircraft was destroyed and the pilot received fatal injuries. The pilot was a qualified glider pilot who had begun gliding ten years previously. However, he had only recently purchased the glider and resumed gliding after a layoff of several years. Stress and fatigue were possible factors in the accident, potential sources being a. the workload required to fly a cross-country route in conditions of poor lift; b. concern about the loss of an important horse sale; c. about sixteen hours driving, including caravan and glider trailer towing, in the 72 hours prior to the accident; and d. pressure to launch on the flight. Before DEPARTURE from Narromine the aircraft altimeters were set to read zero (QFE). Narromine Aerodrome is 782 feet Above Mean Sea Level (AMSL) and Parkes Aerodrome is 1069 feet AMSL. Consequently, an aircraft operating in the Parkes area, with Narromine QFE set on the altimeter subscale, would have approximately 300 feet less terrain clearance than at Narromine. A pilot lacking in currency, under a high workload, and possibly suffering from stress and fatigue, could fail to take this difference into account when considering the minimum altitude required for a safe outlanding. Examination of the wreckage did not reveal any defect that may have contributed to the accident. In March 1988, the wings were reprofiled from the original Wortmann FX67 airfoil sections to modified sections developed from research in USA. There is no evidence to indicate that the wing reprofiling resulted in the need for enhanced pilot skills for safe operation. The pilot was aware of the reprofiled airfoils.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The pilot lacked recent experience.

2. The pilot could have been suffering the effects of stress and fatigue.

3. The pilot misjudged the altitude required and the approach direction during an outlanding.

The forecast for the flight indicated that there was scattered cloud along the flight planned route, with additional cloud around the ranges. The pilot was advised that the weather conditions would be least favourable close to the DEPARTURE aerodrome, with conditions improving as the flight progressed to the south. Approaching the ranges on the Queensland border, the aircraft was climbed to 9000 feet to overfly what the pilot expected would be a small area of cloud. However, the cloud was found to be more extensive and the pilot descended to regain visual contact with the ground. He then found that he was unable to fly out of a valley because of cloud and rain, and elected to carry out a precautionary landing in a paddock. During the landing roll the nose gear was torn off because of the rough surface conditions. An amended area forecast was issued about five minutes before the aircraft departed Archerfield but this was not relayed to the pilot. The amended forecast indicated broken cumulus cloud between 2500 feet and 10000 feet in addition to broken strato-cumulus between 4000 feet and 9000 feet in the area of the accident.

Circumstances:

The pilot reported that he was attempting to land on a short, one-way strip in a quartering tail wind. While on short final the wind speed increased. The aircraft drifted left and sank low on the approach path, finally striking a rock fence just short of the threshold. The left landing gear assembly and the right wheel and axle were dislodged in the impact. The aircraft came to rest some 30 metres from the fence to the left of the strip. The pilot advised that the strip did not meet the requirements of an Authorised Landing Area (ALA) in terms of slope, length, and obstacles. He was not experienced in operating in tail wind conditions into one-way strips and had only landed at this particular strip once before but in different wind conditions.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The pilot was attempting to land on a short sloping strip in hilly terrain. He was not familiar with the strip nor with landing on a steep upslope.

2. The pilot used a flat, low approach technique rather than the correct short field approach procedure.

3. A possible increase in the tail wind was not detected in time to stop the aircraft descending onto a rock fence. This accident was not the subject of an on-scene investigation.

The helicopter was being used to drive cattle across a creek, when one beast broke out of the herd. During an attempt to drive it back, the pilot misjudged the clearance between the main rotor disc and the foliage of a large tree. After the tree strike, the machine was still controllable to the extent that it was landed without any further damage. Post-flight inspection revealed that all three main rotor blades were damaged.